WO2011030506A1

WO2011030506A1 - Nanofiber manufacturing device and nanofiber manufacturing method

Info

Publication number: WO2011030506A1
Application number: PCT/JP2010/005037
Authority: WO
Inventors: 和宜石川; 住田　寛人; 黒川　崇裕; 正伸宮田; 隆敏光嶋
Original assignee: パナソニック株式会社
Priority date: 2009-09-09
Filing date: 2010-08-11
Publication date: 2011-03-17
Also published as: CN102365398B; JP5236042B2; KR20120049174A; US20120013047A1; US8834775B2; JP4763845B2; JP2013047410A; JP2011080186A; US20140342027A1; CN102365398A; JP2011168949A; JP5226151B2

Abstract

Disclosed is a nanofiber manufacturing device (100) for manufacturing nanofibers (301) by electrically stretching a starting material liquid (300) in a space, the nanofiber manufacturing device being provided with: a discharge body (115) which has a plurality of discharge holes (118) for discharging the starting material liquid (300) into the space, the discharge body (115) comprising a front end portion (116) at which openings (119) that are the front ends of the discharge holes (118) are one-dimensionally disposed side by side at predetermined intervals, and two side surface portions (117) which are disposed such that the interval therebetween increases with increasing distance from the front end portion (116) and extend from the front end portion (116) so as to sandwich the discharge holes (118) therebetween; a charged electrode (121) which is disposed at a predetermined interval from the discharge body (115); and a charged power source (122) which applies a predetermined voltage between the discharge body (115) and the charged electrode (121), thereby maintaining high production volumes of nanofibers per unit time and per unit area, and improving and uniforming the quality of nanofibers by suppressing the influence of ion wind.

Description

Nanofiber manufacturing apparatus and nanofiber manufacturing method

The present invention relates to a nanofiber manufacturing apparatus and a nanofiber manufacturing method for manufacturing a fiber (nanofiber) having a fineness of submicron order or nano order by an electrostatic stretching phenomenon.

As a method for producing a thread-like (fibrous) substance made of a resin and having a submicron scale or nanoscale diameter, a method using an electrostatic stretching phenomenon (electrospinning) is known.

This electrostatic stretching phenomenon means that a raw material liquid in which a solute such as a resin is dispersed or dissolved in a solvent is discharged (injected) into the space by a nozzle or the like, and an electric charge is applied to the raw material liquid to charge the space. This is a method of obtaining nanofibers by electrically stretching a raw material liquid in flight.

More specifically, the electrostatic stretching phenomenon is explained as follows. That is, the raw material liquid that has been charged and discharged into the space gradually evaporates the solvent while flying through the space. As a result, the volume of the raw material liquid in flight gradually decreases, but the charge imparted to the raw material liquid remains in the raw material liquid. As a result, the charge density of the raw material liquid in flight through the space gradually increases. Since the solvent continues to evaporate, the charge density of the raw material liquid further increases, and when the repulsive Coulomb force generated in the raw material liquid exceeds the surface tension of the raw material liquid, the raw material liquid explodes. The phenomenon that the film is stretched linearly occurs. This is the electrostatic stretching phenomenon. The electrostatic stretching phenomenon occurs geometrically in succession in the space, and thereby nanofibers made of a resin having a diameter of submicron order or nano order are manufactured.

Improvement of production efficiency can be cited as an exclusive issue for an apparatus for producing nanofibers using the electrostatic stretching phenomenon as described above. For example, it is conceivable to improve the production efficiency of nanofibers by arranging cylindrical nozzles that flow the raw material liquid into the space in a matrix, increasing the amount of nanofibers generated per unit area per unit time. However, in order to increase the amount of nanofibers generated per unit area, it is only necessary to narrow the nozzle arrangement interval. However, if the interval is narrowed, there is a problem with the nanofibers that are generated due to electric field interference between adjacent nozzles. appear. Therefore, in order to solve the problem, the invention described in Patent Document 1 prevents the electric field interference by disposing a separator in a lattice shape between nozzles and applying an AC voltage to the separator.

JP 2008-174867 A

However, in the invention of Patent Document 1, since it is necessary to provide a separator between the nozzles, the interval between the nozzles is increased accordingly, and the production efficiency is reduced. Further, since the nozzle is surrounded by the separator, there is a concern that the charged vapor is likely to stagnate in the enclosed space and adversely affect the manufactured nanofiber. Moreover, it is difficult to make the pressure of the raw material liquid supplied to each nozzle uniform, and it is considered that unevenness occurs in the quality of the manufactured nanofibers.

Furthermore, the present inventors have found that even if a separator is provided, ion wind is generated from the outer peripheral wall of the nozzle and the like, and the ion wind has an adverse effect on the manufactured nanofiber.

Here, ionic wind is considered to be generated by the following phenomenon. That is, when charge is accumulated in a portion having the outer peripheral wall surface, air existing around the portion is ionized. The ionized air is repelled by the charge on the wall surface and jumps out, thereby generating an ion wind that is a flow of air containing ions. In particular, it has been found that ion wind is likely to be generated at a specific portion of the shape of the outer peripheral wall, such as the tip of a protrusion or the tip of a corner.

In addition, when the ion wind intersects with the raw material liquid flying in the space, it is manufactured by disturbing the flight path of the raw material liquid and the nanofiber being manufactured or adversely affecting the charged state of the raw material liquid. The quality of the nanofiber was degraded. It also led to a decrease in nanofiber production efficiency.

The present invention is based on the above-mentioned problems and knowledge, and suppresses electric field interference to maintain a high production amount of nanofibers per unit area per unit time, and suppresses the influence of ion wind to suppress nanofibers. It aims at providing the nanofiber manufacturing apparatus and nanofiber manufacturing method which aim at the improvement and uniformization of the quality of the fiber.

In order to achieve the above object, a nanofiber manufacturing apparatus according to the present invention is a nanofiber manufacturing apparatus that manufactures nanofibers by electrically stretching a raw material liquid in a space. An outflow body having a plurality of outflow holes to be flowed out, and a distal end portion in which openings, which are the front ends of the outflow holes, are arranged one-dimensionally at a predetermined interval, and a mutual interval increases as the distance from the front end portion increases. An outflow body having two side portions that are arranged so as to sandwich the outflow hole from the tip portion, a supply means for supplying a raw material liquid to the outflow hole at a predetermined pressure, and the outflow And a charging power source for applying a predetermined voltage between the outflow body and the charging electrode.

Thereby, the gap between the opening portions of the outflow holes arranged at a predetermined interval is completely filled with the tip portion, so that electric field interference is unlikely to occur. Therefore, the interval between the openings through which the raw material liquid flows can be reduced as much as possible, and the production amount of nanofibers per unit area can be increased.

In addition, since the effluent body has the narrowest tip portion and has a side surface portion that gradually spreads away from the opening portion, the ionic wind is produced even if ion wind is generated from the side surface portion. It is difficult to fly in a direction that adversely affects nanofibers. Furthermore, since the side surface portion is a surface that extends widely in the direction in which the opening portion is disposed, ion wind is unlikely to be generated. Therefore, the effluent can suppress the influence of the ionic wind on the nanofiber.

The outflow body may further include a storage tank that stores the raw material liquid supplied from the supply unit, is connected to the plurality of outflow holes, and supplies the raw material liquid simultaneously to the outflow holes.

According to this, since the raw material liquid supplied by the supply means can be temporarily stored and simultaneously supplied to the outflow hole, the pressure of the raw material liquid supplied to the outflow hole can be made as uniform as possible. It becomes. In addition, the effect can be enjoyed with a simple structure and without increasing the number of parts.

Further, the tip portion may be a rectangle having a predetermined width, and may have a width wider than the diameter of the corresponding opening portion arranged at the tip portion.

According to this, the liquid pool generated around the opening (see the embodiment section for the liquid pool) is sufficiently held by the tip. Then, the raw material liquid flows out thinly from the liquid pool into the space, and an electrostatic stretching phenomenon occurs from there. As described above, since the raw material liquid covers the joint portion between the outflow hole and the tip portion, it is possible to suppress the generation of ion wind.

Furthermore, a collecting means for collecting the nanofibers manufactured in the space and an attracting means for attracting the nanofibers to the collecting means may be provided.

This makes it possible to manufacture functional materials and the like by limiting the targets on which the manufactured nanofibers are deposited.

Furthermore, you may provide the moving means which moves the said outflow body and the said collection means relatively.

This makes it possible to deposit nanofibers uniformly over a wide range.

Further, it is preferable that the outflow body is separable so that a surface formed by the outflow hole is exposed, and the divided outflow body can be assembled.

This improves the maintainability of the spilled body.

In order to achieve the above object, a nanofiber manufacturing method according to the present invention is a nanofiber manufacturing method for manufacturing nanofibers by electrically stretching a raw material liquid in a space. An outflow body having a plurality of outflow holes to be flowed out therein, a front end portion in which openings that are front ends of the outflow holes are arranged one-dimensionally at a predetermined interval, and a distance from each other as the distance from the front end portion increases An outflow step for flowing out the raw material liquid from an outflow body having two side portions extending from the tip end portion so as to sandwich the outflow hole, and a predetermined amount in the outflow hole by the supply means A supply step of supplying a raw material liquid under pressure, a charging electrode arranged at a predetermined interval from the effluent, and a charging step of applying a predetermined voltage between the effluent. Yes.

According to the present invention, it is possible to improve the production efficiency of nanofibers and improve the quality of manufactured nanofibers.

FIG. 1 is a perspective view showing a nanofiber manufacturing apparatus. FIG. 2 is a perspective view with the effluent cut away. FIG. 3 is a perspective view showing the outflow body viewed from the tip side. FIG. 4 is a perspective view showing variations of the tip portion. FIG. 5 is a perspective view showing a nanofiber manufacturing apparatus according to another embodiment. FIG. 6 is an exploded perspective view showing a decomposable effluent. FIG. 7 is a perspective view showing another form of the effluent cut away. FIG. 8 is a perspective view showing another form of the effluent cut away. FIG. 9 is a perspective view showing another form of the effluent cut away. FIG. 10 is a perspective view showing another form of the effluent cut away.

(Embodiment 1)
Next, a nanofiber manufacturing apparatus and a nanofiber manufacturing method according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a nanofiber manufacturing apparatus.

As shown in the figure, the nanofiber manufacturing apparatus 100 is an apparatus that manufactures nanofibers 301 by electrically stretching a raw material liquid 300 in a space, and includes an effluent body 115, a supply means 107, a charging device. An electrode 121 and a charging power source 122 are provided. In the case of the present embodiment, the nanofiber manufacturing apparatus 100 further includes a collecting unit 128 and an attracting unit 104. Furthermore, the nanofiber manufacturing apparatus 100 includes a moving unit 129.

FIG. 2 is a perspective view with the spilled body cut away.

The outflow body 115 is a member that causes the raw material liquid 300 to flow out into the space by the pressure of the raw material liquid 300 (which may include gravity), and includes an outflow hole 118, a tip end portion 116, and a side surface portion 117. Furthermore, a storage tank 113 is provided. The outflow body 115 also functions as an electrode for supplying electric charge to the outflowing raw material liquid 300, and at least a part of the portion in contact with the raw material liquid 300 is formed of a conductive member. In the case of the present embodiment, the entire outflow body 115 is made of metal. In addition, if the kind of metal is provided with electroconductivity, it will not specifically limit, Arbitrary materials, such as brass and stainless steel, can be selected.

The outflow holes 118 are holes through which the raw material liquid 300 flows out into the space, and a plurality of outflow bodies 115 are provided. Moreover, the opening part 119 in the front-end | tip of the outflow hole 118 is arrange | positioned along with the predetermined spacing one-dimensionally. In the case of the present embodiment, the outflow holes 118 are arranged so that the openings 119 are linearly arranged in the same plane, and the axis of the outflow holes 118 intersects at right angles to the direction in which the openings 119 are arranged. Are arranged as follows.

The hole length and hole diameter of the outflow hole 118 are not particularly limited, and a shape suitable for the viscosity of the raw material liquid 300 may be selected. Specifically, the hole length is preferably selected from a range of 1 mm or more and 5 mm or less. The hole diameter is preferably selected from a range of 0.1 mm or more and 2 mm or less. Further, the shape of the outflow hole 118 is not limited to a cylindrical shape, and an arbitrary shape can be selected. In particular, the shape of the opening 119 is not limited to a circular shape, and may be a polygonal shape such as a triangle or a quadrangle, or a shape having a protruding portion such as a star shape.

The intervals at which the openings 119 are arranged may be equally spaced, and the interval between the openings 119 at the end of the effluent 115 is wider than the interval between the openings 119 at the center of the effluent 115. (Narrow) can be arbitrarily determined. In the knowledge currently obtained, when the hole diameter of the opening part 119 is 0.3 mm, the pitch of the opening part 119 can be shortened to about 2.5 mm. It should be noted that these hole diameters and pitches may vary depending on other conditions such as the viscosity of the raw material liquid 300.

Moreover, the openings 119 need not only be arranged on the same straight line, but also need only be arranged one-dimensionally. Here, the term “one-dimensional” refers to a state where the opening 119 is not lined up in the width direction of the rectangle when a marginal region where all the openings 119 are arranged is surrounded by a rectangle. The rectangular region where the opening 119 is disposed has a band shape. In this sense, the opening 119 may be arranged in a zigzag manner, or may be arranged so as to draw a wave such as a sine curve.

The front end portion 116 is a portion of the outflow body 115 where the opening portion 119 of the outflow hole 118 is disposed, and is a portion that connects between the opening portions 119 disposed at a predetermined interval with a smooth surface. In the case of the present embodiment, the distal end portion 116 has an elongated rectangular plane on the surface, and the width thereof is set to be wider than the diameter of the corresponding opening 119. Specifically, for example, the width of the tip 116 varies depending on the diameter of the outflow hole 118, but is set to 1 mm or more in consideration of the diameter of the base of the liquid reservoir 303 (see FIG. 3 described later) being about 1 mm. It is preferable to do.

As shown in FIG. 3, a liquid pool 303 is generated around the opening 119 due to the presence of the tip 116 having a flat surface all around the opening 119. This liquid reservoir 303 is called a tailor cone, which is considered to be generated by the viscosity of the raw material liquid 300 and has a conical shape having a circular bottom surface larger than the opening 119. The liquid reservoir 303 adheres to the front end portion 116 of the outflow body 115 so as to cover the opening 119. Then, the raw material liquid 300 flows out from the conical liquid pool 303 into the space. Thereby, since the opening part 119 does not contact air directly, it becomes possible to suppress the ionic wind generated from the opening part 119.

Note that the tip end portion 116 is not limited to a rectangular flat surface, and the liquid pool 303 may be generated even if it is not a flat surface. For example, as shown to Fig.4 (a), the front-end | tip part 116 may be provided with a curved surface, and as shown in FIG.4 (b), it may be provided with two planes with which the edge part was put together.

Further, when the opening 119 is arranged in a zigzag shape or a corrugated shape as described above, the tip end portion 116 may have a straight band shape or a zigzag shape or a corrugated shape following the arrangement of the opening portion 119.

As described above, the front end portion 116 connects a plurality of openings 119 with a plane (in FIG. 4B, the two ends are connected as described above). It is possible to suppress the electric field interference that occurs when they are arranged. In addition, ion wind generated in a region between the opening 119 and the opening 119 can be suppressed. Therefore, even if the openings 119 are arranged in a narrowed state, the nanofibers 301 can be manufactured satisfactorily, and therefore the production amount of the nanofibers 301 per unit time and unit area can be improved. Become.

Further, since the liquid pool 303 can be held in a good state by the tip portion 116, it is considered that the generation of ion wind can be suppressed and the quality of the nanofiber 301 can be improved and the production efficiency can be improved.

In FIG. 2, the side surface portion 117 is two surfaces disposed so as to sandwich the outflow hole 118, and is a portion of the outflow body 115 that is extended from the distal end portion 116 and disposed in an upright state. Further, the side surface portion 117 is provided so as to extend in the arrangement direction of the outflow holes 118 arranged side by side, and is provided so as to sandwich all the outflow holes 118 between the two side surface portions 117. Further, as shown in FIG. 2, the side surface portions 117 are arranged so that the distance between the side surface portions 117 increases as the distance from the front end portion 116 increases. The sharper the angle between the two side surfaces 117, the more concentrated the charge can be at the tip, and the high quality nanofiber 301 can be manufactured with the raw material liquid 300 at a high charge density. On the other hand, as the angle between the side surfaces 117 becomes sharper, the volume of the storage tank 113 provided in the outflow body 115 becomes smaller, and processing when the storage tank 113 is provided in the outflow body 115 becomes difficult. Considering the above, it is preferable to set the angle between the side portions 117 to about 60 degrees. However, the angle between the both side surfaces 117 in the outflow body 115 is not limited to this.

Note that, as shown in FIGS. 4A and 4B, the boundary between the tip portion 116 and the side surface portion 117 is ambiguous. Further, the shape of the side surface portion 117 may be not only a flat surface but also a curved surface. For example, as shown in FIG. 7, when the outflow hole 118 is provided in the peripheral wall of the cylindrical outflow body 115, the position where the outflow hole 118 is arranged on the peripheral wall of the cylindrical outflow body 115 becomes the front end, and the front end (outflow) The peripheral wall portions at both ends sandwiching the position where the holes 118 are disposed become the side surface portions 117. In this case, the member which comprises the outflow body 115 can be obtained easily, and a process also becomes easy. On the other hand, although the concentration of charges on the tip 116 is inferior to other shapes (for example, the shape of the effluent 115 shown in FIG. 2), the voltage is increased or the position and shape of the charging electrode 121 are devised. Can be covered. As shown in FIG. 8, the side surface portion 117 is a plane, but the portion where the storage tank 113 is generated may be cylindrical. Further, as shown in FIG. 9, the side surface portion 117 has a shape in which the interval between the front end portion 116 is widened on the curved surface, and the portion forming the storage tank 113 is a rectangular cylindrical shape. It doesn't matter. Furthermore, as shown in FIG. 10, the outflow body 115 may be an oval cylindrical body.

The side parts 117 exemplified above are arranged so that the distance between them increases as the distance from the tip part 116 increases. Moreover, it extends along the arrangement direction of the outflow holes 118 so as to sandwich the outflow holes 118 from the front end portion 116. Moreover, the outflow body 115 which combines each part of the illustrated outflow body 115 is also included in this invention. Further, the side surface portion 117 is a portion of the effluent body 115 having a continuous surface in which the distance between each other increases as the distance from the distal end portion 116 increases.

It is desirable that the side surface portion 117 and the front end portion 116 have a smooth surface as a whole and have a shape that suppresses the generation of ion wind without providing a peculiar portion as much as possible (except for the opening portion 119).

The outflow body 115 is provided with the side surface portion 117 so as to suppress the generation of the ionic wind, and even if the ionic wind is generated, the ionic wind can be blown in a direction not intersecting with the raw material liquid 300 flowing into the space. Therefore, the nanofiber 301 can be manufactured in a stable state without being affected by the ion wind.

Further, since the side surface portion 117 is arranged so as to become gradually narrower toward the tip portion 116, electric charges can be easily concentrated on the tip portion 116, and the charges can be efficiently supplied to the raw material liquid 300.

Furthermore, since the space around the opening 119 can be opened widely, it is possible to avoid charging with charged vapor. Further, it is considered that a gas flow along the side surface portion 117 is generated and the charging vapor is actively avoided.

Further, for example, when a wind is generated from the vicinity of the opening 119 toward the downstream side in the outflow direction of the raw material liquid 300, the charged vapor or the ionic wind is excluded from the side surface portion 117 along the raw material liquid 300 in the outflow direction (downward). Thus, the quality of the manufactured nanofiber 301 can be improved.

As shown in FIG. 2, the storage tank 113 is a tank that is formed inside the outflow body 115 and stores the raw material liquid 300 supplied from the supply means 107 (see FIG. 1). The storage tank 113 is connected to the plurality of outflow holes 118 and supplies the raw material liquid 300 to the outflow holes 118 at the same time. In the case of the present embodiment, one storage tank 113 is provided in the outflow body 115, is widely provided from one end portion to the other end portion of the outflow body 115, and is connected to all outflow holes 118.

As described above, the storage tank 113 has a function of temporarily storing the raw material liquid 300 in the vicinity of the outflow holes 118 and supplying the raw material liquid 300 to the plurality of outflow holes 118 with an equal pressure. The raw material liquid 300 can be allowed to flow out from each outflow hole 118 in an even state. Therefore, it is possible to suppress spatial unevenness in the quality of the manufactured nanofiber 301.

As shown in FIG. 1, the supply means 107 is a device that supplies the raw material liquid 300 to the effluent body 115, and includes a container 151 that stores a large amount of the raw material liquid 300 and a pump that conveys the raw material liquid 300 at a predetermined pressure ( (Not shown) and a guide tube 114 for guiding the raw material liquid 300.

The charging electrode 121 is disposed at a predetermined interval from the effluent body 115 and has a conductivity for inducing electric charge to the effluent body 115 when the charging electrode 121 is at a higher voltage or lower voltage than the effluent body 115. It is. In the case of the present embodiment, the charging electrode 121 also functions as an attracting means 104 for attracting the nanofiber 301, is disposed at a position facing the front end portion 116 of the outflow body 115, and is grounded. Therefore, when a positive voltage is applied to the efflux body 115, a negative charge is induced in the charging electrode 121, and when a negative voltage is applied to the efflux body 115, a positive charge is induced in the charging electrode 121. Is done.

The charging power source 122 is a power source that can apply a high voltage to the effluent body 115. In general, the charging power source 122 is preferably a DC power source. In particular, when the charged polarity of the nanofiber 301 is not affected, the charged nanofiber 301 is used to attract the nanofiber 301 with an electrode to which a reverse polarity potential is applied. Is preferably a DC power supply. When the charging power source 122 is a direct current power source, the voltage applied by the charging power source 122 to the charging electrode 121 is preferably set from a value in the range of 5 KV or more and 100 KV or less.

If one electrode of the charging power source 122 is set to the ground potential and the charging electrode 121 is grounded as in the present embodiment, the relatively large charging electrode 121 can be set to the ground state, which improves safety. It becomes possible to contribute to.

Note that a charge may be applied to the raw material liquid 300 by connecting a power source to the charging electrode 121 to maintain the charging electrode 121 at a high voltage and grounding the effluent 115. Further, the charging electrode 121 and the outflow body 115 may be in a connection state in which neither is grounded.

The collecting means 128 is a member that deposits and collects the nanofibers 301 manufactured by the electrostatic stretching phenomenon. In the case of the present embodiment, the collecting means 128 is a sheet of tungsten that is a member that forms a capacitor that is an electronic device, and is supplied in a state of being wound around a roll 127.

Note that the collection means 128 is not limited to this. For example, the collecting means 128 may be made of a rigid plate-like member. Further, when only the deposit of the nanofiber 301 is used, the collection means 128 having a high releasability when the nanofiber 301 is peeled off, such as coating the surface of the collection means 128 with a fluororesin or silicon. There may be.

The attracting means 104 is an apparatus for attracting the nanofibers 301 manufactured in the space to the collecting means 128. In the case of the present embodiment, the attracting means 104 is a metal plate that also functions as the charging electrode 121 and is disposed behind the collecting means 128. The attracting means 104 attracts the charged nanofiber 301 to the collecting means 128 by an electric field. That is, the attracting means 104 is an electrode for generating an electric field for attracting the charged nanofiber 301.

The moving means 129 is a device that relatively moves the outflow body 115 and the collecting means 128. In the case of the present embodiment, the outflow body 115 is fixed, and only the collecting means 128 is moved. Specifically, the transfer means is configured to pull out the long collection means 128 from the roll 127 while winding it, and convey the collection means 128 together with the nanofibers 301 to be deposited.

The moving means 129 may not only move the collecting means 128 but also move the effluent 115 relative to the collecting means 128. The moving means 129 moves the collecting means 128 in a certain direction. Arbitrary operation states, such as reciprocating the outflow body 115, can be exemplified. Further, although the collecting means 128 is moved in a direction orthogonal to the direction in which the openings 119 are arranged, the present invention is not limited to this, and the collecting means 128 is moved in the direction in which the openings 119 are arranged, and the effluent 115 is moved to the opening. You may make it reciprocate in the direction orthogonal to the arrangement direction of 119.

Here, the resin constituting the nanofiber 301 and the solute dissolved or dispersed in the raw material liquid 300 includes polypropylene, polyethylene, polystyrene, polyethylene oxide, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, poly- m-phenylene terephthalate, poly-p-phenylene isophthalate, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyvinyl chloride, polyvinylidene chloride-acrylate copolymer, polyacrylonitrile, polyacrylonitrile-methacrylate copolymer Coalesced, polycarbonate, polyarylate, polyester carbonate, polyamide, aramid, polyimide, polycaprolactone, polylactic acid, polyglycol , Collagen, polyhydroxybutyrate, poly (vinyl acetate), polypeptide or the like and can be exemplified a polymer material such as a copolymer thereof. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and this invention is not limited to the said resin.

Examples of the solvent used for the raw material liquid 300 include volatile organic solvents. Specific examples include methanol, ethanol, 1-propanol, 2-propanol, hexafluoroisopropanol, tetraethylene glycol, triethylene glycol, dibenzyl alcohol, 1,3-dioxolane, 1,4-dioxane, methyl ethyl ketone, methyl isobutyl. Ketone, methyl-n-hexyl ketone, methyl-n-propyl ketone, diisopropyl ketone, diisobutyl ketone, acetone, hexafluoroacetone, phenol, formic acid, methyl formate, ethyl formate, propyl formate, methyl benzoate, ethyl benzoate, benzoate Propyl acid, methyl acetate, ethyl acetate, propyl acetate, dimethyl phthalate, diethyl phthalate, dipropyl phthalate, methyl chloride, ethyl chloride, methylene chloride, chloroform, o-chloroto Ene, p-chlorotoluene, chloroform, carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethane, trichloroethane, dichloropropane, dibromoethane, dibromopropane, methyl bromide, ethyl bromide, propyl bromide, acetic acid, Benzene, toluene, hexane, cyclohexane, cyclohexanone, cyclopentane, o-xylene, p-xylene, m-xylene, acetonitrile, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, pyridine, water Etc. can be listed. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and the raw material liquid 300 used for this invention is not limited to employ | adopting the said solvent.

Furthermore, an inorganic solid material may be added to the raw material liquid 300. Examples of the inorganic solid material include oxides, carbides, nitrides, borides, silicides, fluorides, sulfides, and the like. From the viewpoint of heat resistance and workability of the nanofiber 301 to be manufactured. It is preferable to use an oxide. Examples of the oxide include Al ₂ O ₃ , SiO ₂ , TiO ₂ , Li ₂ O, Na ₂ O, MgO, CaO, SrO, BaO, B ₂ O ₃ , P ₂ O ₅ , SnO ₂ , ZrO ₂ , K. ₂ O, Cs ₂ O, ZnO, Sb ₂ O ₃ , As ₂ O ₃ , CeO ₂ , V ₂ O ₅ , Cr ₂ O ₃ , MnO, Fe ₂ O ₃ , CoO, NiO, Y ₂ O ₃ , Lu ₂ Examples thereof include O ₃ , Yb ₂ O ₃ , HfO ₂ , Nb ₂ O _{5 and the} like. Moreover, the kind selected from the above may be used, and a plurality of kinds may be mixed. In addition, the above is an illustration and the substance added to the raw material liquid 300 of this invention is not limited to the said additive.

The mixing ratio of the solvent and the solute in the raw material liquid 300 varies depending on the type of solvent selected and the type of solute, but the amount of solvent is preferably between about 60 wt% and 98 wt%. Preferably, the solute is 5-30%.

Next, a manufacturing method of the nanofiber 301 using the nanofiber manufacturing apparatus 100 having the above configuration will be described.

First, the raw material liquid 300 is supplied to the effluent 115 by the supply means 107 (supply process). As described above, the raw material liquid 300 is filled in the storage tank 113 of the effluent 115.

Next, the charging electrode 121 is set to a positive or negative high voltage by the charging power source 122. Charge concentrates on the front end portion 116 of the outflow body 115 facing the charging electrode 121, and the charge passes through the outflow hole 118 and is transferred to the raw material liquid 300 flowing out into the space, so that the raw material liquid 300 is charged (charging process). ).

The charging process and the supplying process are performed at the same time, and the charged raw material liquid 300 flows out from the opening 119 of the effluent body 115 (outflow process).

Here, the raw material liquid 300 flowing out from the opening 119 forms a liquid pool 303 that covers the opening 119 and hangs down from the front end 116. The liquid pool 303 is formed for each of a plurality of openings 119, and the raw material liquid 300 hangs down from the tip of the liquid pool 303. By forming the liquid reservoir 303 in this way, it is possible to suppress the generation of ion wind and improve the quality of the manufactured nanofiber 301.

Next, the nanofiber 301 is manufactured by the action of the electrostatic stretching phenomenon on the raw material liquid 300 that has flew in the space to some extent (the nanofiber manufacturing process). Here, the raw material liquid 300 flows out in a strong charged state (high charge density) without being influenced by the ion wind, and the raw material liquid 300 flying from each opening 119 flows out in a thin state without being collected. Thereby, most of the raw material liquid 300 is changed to the nanofiber 301. In addition, since the raw material liquid 300 flows out in a strongly charged state (high charge density), electrostatic stretching occurs over many orders, and a large amount of nanofibers 301 with a small wire diameter are manufactured.

In this state, the nanofiber 301 is attracted to the collecting means 128 by the electric field generated between the attracting means 104 and the outflow body 115 arranged behind the collecting means 128 (attraction process).

As described above, the nanofiber 301 is deposited and collected on the collecting means 128 (collecting step). Since the collecting means 128 is slowly transferred by the moving means 129, the nanofiber 301 is also collected as a long belt-like member extending in the transfer direction.

By using the nanofiber manufacturing apparatus 100 configured as described above and performing the above nanofiber manufacturing method, high quality nanofibers 301 are not spatially uneven while maintaining high production efficiency. It becomes possible to manufacture uniformly.

Note that the present invention is not limited to the above embodiment. For example, as shown in FIG. 5, the charging electrode 121 may be disposed in the vicinity of the effluent 115 and between the effluent 115 and the collecting means 128. Further, in the case of the nanofiber manufacturing apparatus 100 of such an aspect, the attracting means is further provided with a collecting means 128 having air permeability and capable of depositing the nanofiber 301, and generating a gas flow that collects in a predetermined place. 104 may be provided. Specifically, as shown in the figure, the vacuum suction device 141 may be arranged to serve as the attracting means 104 that generates a gas flow from the back of the collecting means 128 toward the collecting means 128. Furthermore, a collection power supply 123 different from (or in common with) the charging power supply 122 is provided, and an electric field method for attracting the nanofibers 301 with an electric field and a gas flow method for attracting with a gas flow can be performed simultaneously or selectively. It doesn't matter if you do.

Further, as shown in FIG. 6, the spilled body 115 may be divided. In particular, it is preferable to employ a split structure that can expose the inner wall surface of the outflow hole 118 because the resin attached to the outflow hole 118 can be easily removed.

The present invention can be used for producing nanofibers, spinning using nanofibers, and producing nonwoven fabrics.

100 Nanofiber production apparatus 104 Attracting means 107 Supplying means 113 Storage tank 114 Guide tube 115 Outflow body 116 Tip part 117 Side face part 118 Outlet hole 119 Opening part 121 Charging electrode 122 Charging power supply 127 Roll 128 Collection means 129 Moving means 151 Container 300 Raw material Liquid 301 Nanofiber

Claims

A nanofiber manufacturing apparatus for manufacturing nanofibers by electrically stretching a raw material liquid in a space,
An outflow body having a plurality of outflow holes through which the raw material liquid flows out into the space, and a distal end portion in which openings that are front ends of the outflow holes are arranged one-dimensionally at predetermined intervals, and is separated from the front end portion And an outflow body having two side portions that are arranged so as to be spaced apart from each other and extend so as to sandwich the outflow hole from the tip portion,
A charging electrode disposed at a predetermined interval from the effluent body;
A nanofiber manufacturing apparatus comprising: a charging power source that applies a predetermined voltage between the effluent and the charging electrode.
The effluent is further
Supply means for supplying a raw material liquid to the outflow hole at a predetermined pressure;
The nanofiber manufacturing apparatus according to claim 1, further comprising a storage tank that stores the raw material liquid supplied from the supply unit, is connected to the plurality of outflow holes, and supplies the raw material liquid to the outflow holes at the same time.
2. The nanofiber manufacturing apparatus according to claim 1, wherein the tip portion is a rectangle having a predetermined width, and has a width wider than the diameter of the corresponding opening arranged at the tip portion.
further,
A collection means for collecting nanofibers produced in space;
The nanofiber manufacturing apparatus according to claim 1, further comprising an attracting unit that attracts the nanofiber to the collecting unit.
further,
The nanofiber manufacturing apparatus according to claim 4, further comprising a moving unit that relatively moves the outflow body and the collecting unit.
2. The nanofiber manufacturing apparatus according to claim 1, wherein the outflow body can be divided so that a surface formed by the outflow hole is exposed, and the divided outflow body can be assembled.
The nanofiber manufacturing apparatus according to claim 1, wherein the tip portion connects the plurality of openings with a smooth surface.
A nanofiber manufacturing method for manufacturing a nanofiber by electrically stretching a raw material liquid in a space,
An outflow body having a plurality of outflow holes for allowing the raw material liquid to flow out into the space, and an opening that is a front end of the outflow hole is arranged one-dimensionally at a predetermined interval, and is separated from the front end According to the outflow step of causing the raw material liquid to flow out from the outflow body having two side portions that are arranged so as to widen each other and extend so as to sandwich the outflow hole from the tip portion,
A nanofiber manufacturing method, comprising: a charging electrode disposed at a predetermined interval from the effluent body; and a charging step of applying a predetermined voltage between the effluent body.
further,
A collection step of collecting nanofibers produced in space by a collection means;
The nanofiber manufacturing method according to claim 8, further comprising an attracting step of attracting the nanofiber to the collecting means.